by Jean Barbet | Feb 6, 2021 | Algebra, Geometry, Non classé
Vector angles are the usual oriented angles of Euclidean plane geometry. Thanks to the resources of naive set theory, they can be defined purely algebraically using an equivalence relation and the vectorial rotations of the plane. The operation of composing rotations... 
by Jean Barbet | Oct 25, 2020 | Geometry, Non classé, Trigonometry
The trigonometric circle allows us to define the cosine, sine and tangent of an oriented angle, and to give an interpretation through Thales’ and Pythagoras’ theorems. Introduction: trigonometry and functions Trigonometry is the study of the relationships... 
by Jean Barbet | Oct 4, 2020 | Algebra, Geometry
The scalar or dot product of two vectors in real space is a real number that takes into account the direction, sense and magnitude of both vectors. 1.The natural scalar product in the Euclidean plane 1.1.From the distance between two points to the scalar product In... 
by Jean Barbet | Jul 6, 2020 | Functions, Geometry
The definition of a circle is simple: it is a set of points located at the same distance from a given point. This distance is called the radius and this point is called the centre of the circle. The circle with centre \((-1,-3/2)\) and radius \(\sqrt 6\) 1. Circles as... 
by Jean Barbet | Jul 1, 2020 | Algebra, Geometry
From Descartes’ analytic approach, which consists in introducing coordinates to represent the points of the plane, and from Cauchy’s construction of the real numbers, we can give a modern representation of the euclidean plane from which we recover...
